Building blocks are customarily made with two or more generally uniformly shaped openings extending between their top and bottom surfaces. Concrete block are perhaps the most common and extensively used building block of the day, and these blocks contain two openings of generally square cross section extending between the top and bottom surfaces. These building block are made in molds having a pair of insert for forming the pair of vertically extending openings; and these inserts are slightly tapered so that they can be withdrawn out of the openings after the block is molded. This configuration of block, therefore, has slightly tapered openings, with one end thereof being slightly smaller than is the other end. Although the invention is not so limited, it is hereafter described as having particular advantages for use for this and other types of building blocks which have openings therethrough that are slightly tapered.
In the usual manner of laying building blocks into walls, one row of building block is laid end to end in a straight line over the top of a suitable foundation. Thereafter, mortar is laid on the top surfaces of the first layer of block, and a second layer of block is pushed down on top of the mortar that has been placed on the bottom row of blocks. A straight edge is placed vertically against the side face of the bottom row of blocks, and the top row of blocks is moved laterally so that its front face just engages the straight edge. Thereafter, excess mortar is scraped from the joints between the tiers of blocks. The process of "buttering" the mortar on top of each block and carefully aligning each block is a laborious, time consuming task, which both limits the number of blocks which can be put in place, and makes the process too exacting for most amateurs.
Another problem that is encountered with building blocks is that they presently are held in place only by the mortar in the joints and any movement of the wall opens these concrete mortar joints to allow weather to penetrate into the internal opening and perhaps all of the way through the block wall.
A principle object of the present invention therefore, is the provision of a new and improved type of block aligning insert which will automatically center rows of blocks on top of each other.
Another object of the invention is the provision of a new and improved type of alignment insert which will key the building blocks laterally, so that flexible mortar bonding materials can be used in the joints to accommodate a slight amount of movement of the blocks, and thereby provide a more weather-proof construction.
A further object of the invention is the provision of a new and improved insert of the above described type which is simple in design, rugged in construction, and inexpensive to manufacture; and which will key the individual blocks to an exact, aligning, position with provision for uniform joints therebetween, so that the joint material can be trowled into place after a large number of the blocks have been keyed together.
Further objects and advantages of the present invention will become apparent to those skilled in the art from the following description of several preferred embodiments, described with reference to the accompanying drawings forming a part of this specification.